coldroom too much ice on evaporator

[stathis]

hi everyone!r404 coldroom has ice build up every 10 days.during winter it was working fine and now there is a big problem.working temperature of coldroom is between 0-2 celsius.thans in advance!

[goshen]

hi everyone!r404 coldroom has ice build up every 10 days.during winter it was working fine and now there is a big problem.working temperature of coldroom is between 0-2 celsius.thans in advance!
Hi :

u probably dont have a DEFROST SEQUENCE u should add one.(compressor standby)
are your pressures okay??
is your txv set ok?
do u have head pressure control?
does compressor cycle off when door is open?
if this is the first year u have a problem ,and u charged the unit durring the winter,u might be low on refregerant.
good luck
:D

[stathis]

dear friend yes its the first year the system works it has defrost system with heaters and it works everu 8 hours for 10 minutes.working presure for r404? i think i need charging but the sight glass fills completely when its working...thanks in advance!

[goshen]

dear friend yes its the first year the system works it has defrost system with heaters and it works everu 8 hours for 10 minutes.working presure for r404? i think i need charging but the sight glass fills completely when its working...thanks in advance!
Hi
yes by giving us the working pressure corilated with the room temp at that moment ,u could determin if you are working correctly ,and i think u should check your txv setting.:D
good luck

[Sandro Baptista]

hi everyone!r404 coldroom has ice build up every 10 days.during winter it was working fine and now there is a big problem.working temperature of coldroom is between 0-2 celsius.thans in advance!

Check the evaporating temperature. Does the defrost is completed? Does the doors remain very time long open? Does the infiltration air is exterior from the exterior of the building? In the summer there is more water vapour content on the air (higher absolut humidity). Maybe you need an air curtain or something like that.

Regards

[samisonfire]

I agree with Sandro, humidity is going to be much lower in the winter.
Obviously check for any air gaps on doors, etc..
Also, i've always been told to have 4 defrosts a day, every 6 hours.

[hm1982]

hey.did u check the door seals are not cracked,the right size for the door,does the door shut ok

[Aik]

In addition check fin spacing of evaporator may be small distance beetwin fins.


Also, i've always been told to have 4 defrosts a day, every 6 hours.
Or increase defrosting time...

[ZeroTolerance]

I am a facilities manager for OSI Restaurants and most our refrigeration operates off of R-404. I had a walk in freezer do the same thing. Make sure the condensor fans on the roof are operating correctly

[ZeroTolerance]

sorry misread your thread. Thought you were having ice build up on the evaporator. But ya sounds like an insulating problem to me

[Sandro Baptista]

I agree with Sandro, humidity is going to be much lower in the winter.
Obviously check for any air gaps on doors, etc..
Also, i've always been told to have 4 defrosts a day, every 6 hours.

Stathis,
How much time do you have the defrost time for each cycle? Does the defrost is totally completed after the end of the evaporator?

Also if you have the evaporators next to the acess door (mounted on that wall) that wouldn't help to prevent ice formation on the fin coils of the evaporator.

[mianrizwan]

1) Shortage of refregerant
2) Txv not adjusted
3) Heater not working